View clinical trials related to Nicotine Dependence.
Filter by:Background: - Functional and structural magnetic resonance imaging (MRI) techniques have allowed researchers to map and study how the brain works when at rest and when engaged in specific tasks. MRI scans have provided more information about how drugs affect the brain, and about how drug addiction changes the brain and influences behavior, mood, and thinking processes. To better understand the underlying mechanism of drug addiction and to develop strategies for more effective treatment, researchers are interested in developing new MRI techniques to study the effects of addiction on the brain. Objectives: - To develop new functional and structural MRI techniques, and to evaluate their potential use in brain imaging studies related to addiction. Eligibility: - Individuals between 18 and 80 years of age. - Participants may be smokers or nonsmokers, and may use drugs or not use drugs. Design: - During the initial screening, participants will complete questionnaires about family and personal history, drug use, and other information as required by the researchers. Participants who will be asked to complete tasks during the MRI scan will be shown how to perform these tasks before the scanning session. - Before each study session, participants may be asked to complete some or all of the following: questions about their drug use during the last week, a breathalyzer test, a urine drug-use assessment, a urine pregnancy test, or a measure of carbon monoxide. Participants will also provide blood samples before the start of the scan. - For each scanning session, participants will have an MRI scan that will last approximately 2 hours. - MRI scans may include specific tasks to be performed during the scan, or an experiment that studies the brain's response to carbon dioxide.
Background: - Some people with schizophrenia have problems with their working memory and paying attention for extended periods. These difficulties cannot be treated with antipsychotic medications or with many standard therapies. - The prevalence of cigarette smoking among individuals with schizophrenia is about three times higher than in the general population. Research has shown that nicotine, the addictive component found in cigarettes, can help improve attentional and working memory performance. Researchers are interested in learning more about whether there may be an overlap in the cognitive functions beneficially affected by nicotine and areas of dysfunction in individuals with schizophrenia. Objectives: - To evaluate the potential of transdermal nicotine to alleviate cognitive deficits in schizophrenia, and to determine whether naturally maintained cigarette-smoking, in comparison, is an effective self-medication. - To gather preliminary data on genetics that may account for individual and group differences in the performance effects of nicotine. Eligibility: - Current smokers (25 or more cigarettes per week for at least 1 year) between 18 and 55 years of age who are either healthy volunteers or have been diagnosed with schizophrenia/schizoaffective disorder. Design: - The study will require five visits to the research center, with an initial screening visit, a training session, and three test sessions. Ideally, all visits will occur 1 week apart. - Training session: Participants will receive training on the types of computerized cognitive and attentional behavior tests that will be given during the active portion of the study. Participants will also fill out questionnaires on nicotine use and other alcohol and drug use. - Test sessions: Participants will be assigned to random groups and will complete tests that assess cognitive performance (a) while maintaining their usual smoking behavior, (b) after minimal deprivation (3.5 hours without smoking) while wearing a placebo patch, and (c) under the influence of a standard nicotine patch. The order of these sessions will be different for individual participants. - Participants will provide blood samples throughout the research study for evaluation purposes.
Background: - Many cigarette smokers claim that smoking helps them stay alert and improves their concentration, and have reported problems in attention and concentration after quitting smoking. Some research has indicated that nicotine can enhance certain aspects of attention and memory in humans. However, more research is needed to determine how nicotine affects different elements of the brain's ability to pay attention. Knowing which aspects of attention are affected by nicotine may help produce new medications and therapies to help people successfully stop smoking. Objectives: - To investigate the dose-related effects of nicotine on the ability to pay attention in smokers and nonsmokers. - To compare the effects of nicotine in smokers and nonsmokers. Eligibility: - Individuals between 18 and 50 years of age who are either current smokers (at least 15 cigarettes per day on average for at least 2 years) or healthy, nonsmoking volunteers. Design: - The study will consist of one training session and three testing sessions. Each session will last about 2 hours. - The training session will introduce participants to the study tests and evaluate their tolerance of the two levels of nicotine nasal spray used in the study. Smokers will receive the higher dose of nicotine to introduce them to the effects of the spray. Nonsmokers will be given first the lower dose of the spray, followed by higher dose at least 30 minutes later. Nonsmoking participants who cannot tolerate the higher dose will not continue in the study. - At the start of each testing session, smokers will have one cigarette to standardize the time of the most recent exposure to nicotine. - During the testing sessions, participants will receive a placebo spray, a lower dose of nicotine, or a higher dose of nicotine, and then will be asked to perform tests that evaluate mood, attention, and performance.
Background: - Treatment for nicotine addiction is characterized by high rates of relapse. New treatment therapies for nicotine addiction are exploring the use of brain scanning equipment to control and decrease nicotine and cigarette cravings. - Transcranial magnetic stimulation (TMS) uses magnetic pulses to stimulate the brain. These pulses can change activity in parts of the brain. Researchers are interested in determining whether TMS delivered in single pulses can decrease activity in the parts of the brain that respond to nicotine craving. Objectives: - To determine whether single pulse TMS can reduce cue-induced nicotine craving and use in cigarette smokers. Eligibility: - Individuals 18 years of age and older who are physically healthy and have smoked 10 or more cigarettes per day for at least 1 year. - A small group of healthy nonsmoking control subjects 18 years of age and older will also participate in the study. Design: - The study will involve seven study visits and two follow-up visits. The control participants will have only two visits: one with a magnetic resonance imaging (MRI) scan and one with TMS to evaluate brain function and response. - Participants will have an initial assessment about tobacco use habits and craving patterns, and will provide blood and urine samples before beginning the study. - Participants will have two initial MRI brain scans. The first scan will look at the structure of the brain at rest. During the other scan, participants will look at images related to and not related to cigarette smoking. - The single pulse TMS sessions (with either actual TMS or inactive [sham] TMS) will be held daily for 5 consecutive days. Magnetic pulses will be triggered by cigarette-related picture cues and delivered at varying intervals before the participant sees a cigarette-related picture. During these testing visits, researchers will ask questions related to tobacco use and craving, and collect urine and breath samples for further study. - Participants will have two follow-up visits, 1 week and 2 weeks after the TMS sessions, to evaluate memory and mood, and will have one final MRI brain scan at the end of the study.
Background: - The prevalence of cigarette smoking among individuals with schizophrenia is noticeably higher than in the general population, and smoking cessation attempts frequently are unsuccessful in this population. Little is known about the effects of cigarette/nicotine craving in individuals with schizophrenia. Researchers are interested in learning more about how craving affects people with schizophrenia and developing new ways to treat cravings and improve the effectiveness of smoking cessation therapies and treatments. - In recent years, virtual reality (VR) has been studied to determine whether it can be used to induce craving by using life-like cue settings. VR cues involving cigarette use, including images of cigarettes and scent cues of tobacco smoke, may be used to elicit craving in smokers. Researchers are interested in learning more about how individuals with schizophrenia respond to specific VR cues and settings. Objectives: - To determine the feasibility of using a contextual real-world paradigm using virtual reality involving cigarette smoking in people with schizophrenia. - To examine if virtual reality cues will elicit craving in smokers with schizophrenia. Eligibility: - Current smokers (five or more cigarettes per day for at least 1 year) between 18 and 45 years of age who have been diagnosed with schizophrenia/schizoaffective disorder. Design: - The study will involve three sessions, with an initial screening visit, a test session, and a follow-up session. - Screening visit: Participants will be screened with a medical and psychiatric history, and will answer questions about smoking history, current smoking habits and craving patterns, and general anxiety levels. This session will also introduce participants to the operation and use of the VR equipment. Participants who are comfortable using the VR system will return within 2 days for the test session. - Test session: Participants will use the VR equipment to view neutral scenes and scenes that are designed to elicit cravings for cigarettes. After viewing each scene, participants will answer questions about their overall mood, anxiety levels, and any cigarette cravings they may have. - Follow-up session: Participants will return 1 week after the VR session to answer questions about mood, anxiety levels, and current smoking habits and craving patterns.
Background: - Self-report and biochemical verification are used to determine smoking status in treatment trials and clinical research. Each method has merits and limitations that make it appropriate for particular situations. Participants who feel social pressure to report tobacco abstinence may provide unreliable self-reporting results. Biochemical verification using breath carbon monoxide (CO) is a more reliable indicator, but several biological and environmental factors (including exposure to secondhand smoke) can affect the sensitivity and specificity of breath CO measurement. - An ideal biomarker of smoking status is cotinine, the major metabolite of nicotine. Cotinine levels found in blood, urine, and saliva can be used to distinguish between smokers and nonsmokers, as well as between light and heavy smokers. Researchers are interested in using cotinine assessments to develop suitable breath CO cutoff levels to categorize different types of smokers and nonsmokers for use in future research. Objectives: - To determine a breath carbon monoxide (CO) cutoff level that optimally discriminates between heavy and light smokers and nonsmokers who are and who are not exposed to environmental tobacco smoke. Eligibility: - Individuals between 18 and 64 years of age who fall into one of the following groups: - current smokers reporting more than 10 cigarettes per day for at least 6 months - current smokers reporting 10 or fewer cigarettes per day for at least 6 months - nonsmokers reporting regular environmental exposure to tobacco smoke - nonsmokers reporting limited or no exposure to tobacco smoke Design: - The study will involve a single outpatient session. - Participants will provide breath CO, urine, and saliva samples, and will complete several smoking-related questionnaires on smoking history, current craving levels, and perceived level of nicotine dependence.
This is a molecular imaging research study designed to examine how much nicotine gets into the brain before and after vaccination with NicVAX, a nicotine vaccine developed by Nabi Biopharmaceuticals. NicVAX (Nicotine Conjugate Vaccine) is an investigational vaccine designed as an aid to smoking cessation and long-term abstinence, as well as an aid to prevent relapses of a treated smoker. In this project we want to understand the degree to which NicVAX administration changes how much nicotine enters the brain in smokers.
To determine if the mu opioid receptor gene (OPRM1) A118G polymorphism moderates the subjective-rewarding effects of intravenous (IV) nicotine in male and female smokers. The subjective effects of nicotine will be measured with a Drug Effects Questionnaire, including the ratings of "good effects" and "drug liking". We hypothesize that smokers with the AG/GG genotype for the OPRM1 A118G will have attenuated subjective-rewarding effects from IV nicotine when compared to those with AA genotype.
This study will investigate the underlying neurobiology of differences between male and female smokers. Research suggests that women are less responsive to nicotine replacement therapy (NRT) than men and more responsive to the sensory and behavioral aspects of smoking. This study proposed that male smokers will have a greater response to NRT demonstrated by reduced withdrawal symptoms, craving, and less blood-oxygen-level dependent functional magnetic resonance imaging (BOLD FMRI) regional brain activation in response to nicotine-cues as compared to female smokers treated with NRT. Additionally, female smokers will have a greater response to denicotinized cigarettes with decreased withdrawal symptoms, craving, and less BOLD fMRI activation in response to nicotine-cues as compared to male smokers.
Unfortunately, the investigators still need to assess and identify novel ways to help people quit smoking. Differences between people in terms of how fast they metabolize nicotine influences response to transdermal nicotine patches, the most popular nicotine dependence treatment, and it affects plasma levels of nicotine from treatment. These studies suggest that fast metabolizers of nicotine may show better quit rates if they receive higher doses of transdermal nicotine. This preliminary study is designed to assess, for the first time, whether fast nicotine metabolizers show higher quit rates if given high dose transdermal nicotine, versus standard dose. The study findings may help to support a subsequent large trial to assess standard versus high dose transdermal nicotine for slow versus fast metabolizers of nicotine, which may lead to a more personalized approach to treating nicotine dependence using the nicotine patch to improve therapeutic benefits of transdermal nicotine.